The big committ:
[libfirm] / ir / be / beirgmod.c
index 444e69e..a2b2c1f 100644 (file)
@@ -1,5 +1,19 @@
+/**
+ * This file contains the following IRG modifications for be routines:
+ * - backend dominance information
+ * - SSA construction for a set of nodes
+ * - insertion of Perm nodes
+ * - empty block elimination
+ * - a simple dead node elimination (set inputs of unreachable nodes to BAD)
+ *
+ * Author:      Sebastian Hack, Daniel Grund, Matthias Braun, Christian Wuerdig
+ * Date:        04.05.2005
+ * Copyright:   (c) Universitaet Karlsruhe
+ * Licence:     This file protected by GPL -  GNU GENERAL PUBLIC LICENSE.
+ * CVS-Id:      $Id$
+ */
 #ifdef HAVE_CONFIG_H
-#include "config.h"
+#include <config.h>
 #endif
 
 #include <stdlib.h>
@@ -40,8 +54,8 @@
 
 #include "beirgmod.h"
 
-#define DBG_MODULE "firm.be.irgmod"
 #define DBG_LEVEL SET_LEVEL_0
+DEBUG_ONLY(static firm_dbg_module_t *dbg = NULL;)
 
 /*
   ____                  _
 
 */
 
-
+/**
+ * The dominance frontier for a graph.
+ */
 struct _be_dom_front_info_t {
-  pmap *df_map;
+       pmap *df_map;         /**< A map, mapping every block to a list of its dominance frontier blocks. */
+       struct obstack obst;  /**< An obstack holding all the frontier data. */
 };
 
 /**
@@ -71,101 +88,114 @@ struct _be_dom_front_info_t {
  */
 static INLINE ir_node *get_idom(ir_node *bl)
 {
-  ir_node *idom = get_Block_idom(bl);
-  return idom == NULL ? bl : idom;
+       ir_node *idom = get_Block_idom(bl);
+       return idom == NULL ? bl : idom;
 }
 
-static void compute_df(ir_node *n, pmap *df_map)
+/**
+ * Compute the dominance frontier for a given block.
+ *
+ * @param blk   the block where the calculation starts
+ *
+ * @return the list of all blocks in the dominance frontier of blk
+ */
+static ir_node **compute_df(ir_node *blk, be_dom_front_info_t *info)
 {
-  ir_node *c;
-  const ir_edge_t *edge;
-  pset *df = pset_new_ptr_default();
-
-  /* Add local dominance frontiers */
-  foreach_block_succ(n, edge) {
-    ir_node *y = edge->src;
-
-    if(get_idom(y) != n)
-      pset_insert_ptr(df, y);
-  }
-
-  /*
-   * Go recursively down the dominance tree and add all blocks
-   * int the dominance frontiers of the children, which are not
-   * dominated by the given block.
-   */
-  for(c = get_Block_dominated_first(n); c; c = get_Block_dominated_next(c)) {
-    pset *df_c;
-    ir_node *w;
-
-    compute_df(c, df_map);
-    df_c = pmap_get(df_map, c);
-
-    for(w = pset_first(df_c); w; w = pset_next(df_c)) {
-      if(get_idom(w) != n)
-        pset_insert_ptr(df, w);
-    }
-  }
-
-  pmap_insert(df_map, n, df);
+       ir_node *c;
+       const ir_edge_t *edge;
+       ir_node **df_list = NEW_ARR_F(ir_node *, 0);
+       ir_node **df;
+       int len;
+
+       /* Add local dominance frontiers */
+       foreach_block_succ(blk, edge) {
+               ir_node *y = edge->src;
+
+               if (get_idom(y) != blk) {
+                       ARR_APP1(ir_node *, df_list, y);
+               }
+       }
 
+       /*
+        * Go recursively down the dominance tree and add all blocks
+        * into the dominance frontiers of the children, which are not
+        * dominated by the given block.
+        */
+       for (c = get_Block_dominated_first(blk); c; c = get_Block_dominated_next(c)) {
+               int i;
+               ir_node **df_c_list = compute_df(c, info);
+
+               for (i = ARR_LEN(df_c_list) - 1; i >= 0; --i) {
+                       ir_node *w = df_c_list[i];
+                       if (get_idom(w) != blk)
+                               ARR_APP1(ir_node *, df_list, w);
+               }
+       }
+
+       /* now copy the flexible array to the obstack */
+       len = ARR_LEN(df_list);
+       df = NEW_ARR_D(ir_node *, &info->obst, len);
+       memcpy(df, df_list, len * sizeof(df[0]));
+       DEL_ARR_F(df_list);
+
+       pmap_insert(info->df_map, blk, df);
+       return df;
 }
 
 be_dom_front_info_t *be_compute_dominance_frontiers(ir_graph *irg)
 {
-  be_dom_front_info_t *info = xmalloc(sizeof(*info));
+       be_dom_front_info_t *info = xmalloc(sizeof(*info));
 
-  edges_assure(irg);
-  info->df_map = pmap_create();
-  compute_doms(irg);
-  compute_df(get_irg_start_block(irg), info->df_map);
+       edges_assure(irg);
+       obstack_init(&info->obst);
+       info->df_map = pmap_create();
+       assure_doms(irg);
+       (void)compute_df(get_irg_start_block(irg), info);
 
-  return info;
+       return info;
 }
 
 void be_free_dominance_frontiers(be_dom_front_info_t *info)
 {
-  pmap_entry *ent;
-
-  for(ent = pmap_first(info->df_map); ent; ent = pmap_next(info->df_map))
-    del_pset(ent->value);
-
-  pmap_destroy(info->df_map);
-  free(info);
+       obstack_free(&info->obst, NULL);
+       pmap_destroy(info->df_map);
+       free(info);
 }
 
-pset *be_get_dominance_frontier(be_dom_front_info_t *info, ir_node *block)
+/* Get the dominance frontier of a block. */
+ir_node **be_get_dominance_frontier(be_dom_front_info_t *info, ir_node *block)
 {
-  return pmap_get(info->df_map, block);
+       return pmap_get(info->df_map, block);
 }
 
 static void determine_phi_blocks(pset *copies, pset *copy_blocks, pset *phi_blocks, be_dom_front_info_t *df_info)
 {
        ir_node *bl;
-       pdeq *worklist = new_pdeq();
-       FIRM_DBG_REGISTER(firm_dbg_module_t *dbg, DBG_MODULE);
+       waitq *worklist = new_waitq();
 
        /*
         * Fill the worklist queue and the rest of the orig blocks array.
         */
-       for(bl = pset_first(copy_blocks); bl; bl = pset_next(copy_blocks)) {
-               pdeq_putr(worklist, bl);
+       for (bl = pset_first(copy_blocks); bl; bl = pset_next(copy_blocks)) {
+               waitq_put(worklist, bl);
        }
 
        while (!pdeq_empty(worklist)) {
-               ir_node *bl = pdeq_getl(worklist);
-               pset *df    = be_get_dominance_frontier(df_info, bl);
+               ir_node *bl  = waitq_get(worklist);
+               ir_node **df = be_get_dominance_frontier(df_info, bl);
+               int i;
 
                ir_node *y;
 
                DBG((dbg, LEVEL_3, "dom front of %+F\n", bl));
                DEBUG_ONLY(
-                       for (y = pset_first(df); y; y = pset_next(df))
-                               DBG((dbg, LEVEL_3, "\t%+F\n", y))
+                       for (i = ARR_LEN(df) - 1; i >= 0; --i)
+                               DBG((dbg, LEVEL_3, "\t%+F\n", df[i]))
                );
 
-               for(y = pset_first(df); y; y = pset_next(df)) {
-                       if(!pset_find_ptr(phi_blocks, y)) {
+               for (i = ARR_LEN(df) - 1; i >= 0; --i) {
+                       y = df[i];
+                       if (!pset_find_ptr(phi_blocks, y)) {
                                pset_insert_ptr(phi_blocks, y);
 
                                /*
@@ -176,12 +206,12 @@ static void determine_phi_blocks(pset *copies, pset *copy_blocks, pset *phi_bloc
                                set_irn_link(y, NULL);
 
                                if(!pset_find_ptr(copy_blocks, y))
-                                       pdeq_putr(worklist, y);
+                                       waitq_put(worklist, y);
                        }
                }
        }
 
-       del_pdeq(worklist);
+       del_waitq(worklist);
 }
 
 /*
@@ -222,7 +252,6 @@ static ir_node *search_def(ir_node *usage, int pos, pset *copies, pset *copy_blo
 {
        ir_node *curr_bl;
        ir_node *start_irn;
-       FIRM_DBG_REGISTER(firm_dbg_module_t *dbg, DBG_MODULE);
 
        curr_bl = get_nodes_block(usage);
 
@@ -333,8 +362,6 @@ static void fix_usages(pset *copies, pset *copy_blocks, pset *phi_blocks, pset *
                int pos;
        } *outs;
 
-       FIRM_DBG_REGISTER(firm_dbg_module_t *dbg, DBG_MODULE);
-
        obstack_init(&obst);
 
        /*
@@ -345,9 +372,11 @@ static void fix_usages(pset *copies, pset *copy_blocks, pset *phi_blocks, pset *
        for (irn = pset_first(copies); irn; irn = pset_next(copies)) {
                const ir_edge_t *edge;
                foreach_out_edge(irn, edge) {
-                       if (!pset_find_ptr(ignore_uses, get_edge_src_irn(edge))) {
+                       ir_node *src = get_edge_src_irn(edge);
+                       /* ignore all users from ignore_uses or keep-alives (user is End node) */
+                       if (! pset_find_ptr(ignore_uses, src) && ! is_End(src)) {
                                struct out tmp;
-                               tmp.irn = get_edge_src_irn(edge);
+                               tmp.irn = src;
                                tmp.pos = get_edge_src_pos(edge);
                                obstack_grow(&obst, &tmp, sizeof(tmp));
                                n_outs++;
@@ -421,7 +450,7 @@ static void remove_odd_phis(pset *copies, pset *unused_copies)
                sched_remove(irn);
        }
 }
-#endif
+#endif /* if 0 */
 
 void be_ssa_constr_phis_ignore(be_dom_front_info_t *info, be_lv_t *lv, int n, ir_node *nodes[], pset *phis, pset *ignore_uses)
 {
@@ -453,7 +482,6 @@ void be_ssa_constr_set_phis_ignore(be_dom_front_info_t *df, be_lv_t *lv, pset *n
        int save_optimize      = get_optimize();
        int save_normalize     = get_opt_normalize();
        int phis_set_created   = 0;
-       FIRM_DBG_REGISTER(firm_dbg_module_t *dbg, DBG_MODULE);
 
        ir_node *irn;
 
@@ -546,7 +574,6 @@ ir_node *insert_Perm_after(const arch_env_t *arch_env,
        ir_node *bl     = is_Block(pos) ? pos : get_nodes_block(pos);
        ir_graph *irg   = get_irn_irg(bl);
        pset *live      = pset_new_ptr_default();
-       FIRM_DBG_REGISTER(firm_dbg_module_t *dbg, "be.node");
 
        ir_node *curr, *irn, *perm, **nodes;
        int i, n;
@@ -576,7 +603,7 @@ ir_node *insert_Perm_after(const arch_env_t *arch_env,
        free(nodes);
 
        curr = perm;
-       for(i = 0; i < n; ++i) {
+       for (i = 0; i < n; ++i) {
                ir_node *copies[2];
                ir_node *perm_op = get_irn_n(perm, i);
                const arch_register_t *reg = arch_get_irn_register(arch_env, perm_op);
@@ -634,10 +661,14 @@ void extreme_liverange_splitting(struct _be_chordal_env_t *cenv)
        obstack_free(&c.obst, NULL);
 }
 
+/**
+ * Post-block-walker: Find blocks containing only one jump and
+ * remove them.
+ */
 static void remove_empty_block(ir_node *block, void *data) {
-       ir_graph *irg;
        const ir_edge_t *edge, *next;
        ir_node *node;
+       int *changed = data;
        ir_node *jump = NULL;
 
        assert(is_Block(block));
@@ -669,16 +700,26 @@ static void remove_empty_block(ir_node *block, void *data) {
 
        set_Block_cfgpred(block, 0, new_Bad());
        sched_remove(jump);
+       *changed = 1;
+}
+
+/* removes basic blocks that just contain a jump instruction */
+int be_remove_empty_blocks(ir_graph *irg) {
+       int changed = 0;
 
-       irg = get_irn_irg(block);
-       set_irg_doms_inconsistent(irg);
-       set_irg_extblk_inconsistent(irg);
-       set_irg_outs_inconsistent(irg);
+       irg_block_walk_graph(irg, remove_empty_block, NULL, &changed);
+       if (changed) {
+               /* invalidate analysis info */
+               set_irg_doms_inconsistent(irg);
+               set_irg_extblk_inconsistent(irg);
+               set_irg_outs_inconsistent(irg);
+       }
+       return changed;
 }
 
-/**
- * removes basic blocks that just contain a jump instruction
- */
-void be_remove_empty_blocks(ir_graph *irg) {
-       irg_block_walk_graph(irg, remove_empty_block, NULL, NULL);
+void be_init_irgmod(void)
+{
+       FIRM_DBG_REGISTER(dbg, "firm.be.irgmod");
 }
+
+BE_REGISTER_MODULE_CONSTRUCTOR(be_init_irgmod);